66561801750795 has 64 divisors (see below), whose sum is σ = 115332224160384. Its totient is φ = 32586195333120.

The previous prime is 66561801750709. The next prime is 66561801750811. The reversal of 66561801750795 is 59705710816566.

It is not a de Polignac number, because 66561801750795 - 2³¹ = 66559654267147 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 25075687 + ... + 27602783.

It is an arithmetic number, because the mean of its divisors is an integer number (1802066002506).

Almost surely, 2^{66561801750795} is an apocalyptic number.

66561801750795 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

66561801750795 is a deficient number, since it is larger than the sum of its proper divisors (48770422409589).

66561801750795 is a wasteful number, since it uses less digits than its factorization.

66561801750795 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2527872.

The product of its (nonzero) digits is 95256000, while the sum is 66.

The spelling of 66561801750795 in words is "sixty-six trillion, five hundred sixty-one billion, eight hundred one million, seven hundred fifty thousand, seven hundred ninety-five".